The study will be a multi-center, prospective study enrolling a cohort of about 2,000 patients with AIDS. Patients with best-corrected visual acuity of at least 20/100 in at least one eye and with a diagnosis of AIDS according to the 1993 CDC diagnostic criteria for AIDS will be eligible for enrollment. The outcome of primary interest are incidence of CMV retinitis and other ocular complications, and mortality. Outcomes of secondary interest include incidence of sequelae of AIDS related eye disease (e.g., retinal detachments), incidence of complications of therapy, and long-term outcomes of ocular complications (e.g., visual function, quality of life).